Island



A, c. MAXFIELD May 23. l 933.

' HOLDER mm TO Original d J 1y 11 FOR File u INVENTOR. #596501- 'MIfie/di 4 v ATTORNEYS.

, Original No. 1,861,504, dated June 7, 1932, Serial No. 377,428, filed view showing the Reisoued May 23, 1933 UNITED STATES PATENT OFFICE ARTHUR o. IAIFJELD, or omsrou,

RHODE ISLAND, ASSIGNOR TO BROWN & SHARP]! RHODE ISLAND HOLDER FOR MACHINE TOOLS July 11, 1929. Renewed April 28, 1882.

Application for reissue filed January 21, 1938. Serial No. 652,963.

My present invention has particular reference in its tool holder. 7

One object of my invention is to provide a tool holder so constructed that tool shanks mounted therein may therefrom.

A second object of my invention is to utilize a tool holder which has a socket with a non-stickin taper for receiving tool shanks.

A third 0 ject is to provide a positive lock for a tool shank inserted within the holder.

A fourth object of my invention is the provision of a floating seat in the tool holder to prevent complete seating of the tool shank therein until the locking elements are in locking alignment.

A fifth object is to utilize the movement of a manually operable cam lock for completing the tool shank seating movement and for locking the tool shank within the tool holder.

A further object is to limit the movement relates to tools, and to securing the tool of the cam lock between open and locked po sitions.

Other objects and advantageous features will be readily apparent from the detailed description following, in conjunction with the accompanying drawing, and will be particularly pointed out in the appended claims.

In the drawing, Figure 1 is an assembly improved tool holder positioned in a standard spindle, with a'machine tool locked therein;

Figure 2 is a sectional elevation of the tool holder;

Figure '3 is a section thereof on the line 3-3 of Figure 1;

Figure 4'is a perspective viewof the lockin cam; and v igure 5 is a section on the line 55 of Figure 3, showing the extent of the movement limiting groove.-

The tool holders heretofore used for hold ing machine tools of relatively small shank diameters have had a low for receivin the tool shan which is forced in with a riving fit. To remove the tool it has heretofore been necessary to use a drift be readily removed pitchxtaper socket.

pin or to drive the tool out, thus requiring the removal of thecholder from the spindle. Under certain circumstances, it has also happened that a tool shank seated in the spindle for an extended period, often becomes frozen to the spindle, and removal therefrom is attended with great difliculty; chanics, to obviate this difliculty, periodical ly remove, oil, and reset the tools within their support or mounting.

have overcome these disadvantages by providing a holder with a' short, abrupt, nonsticking taper and with a locking drive cam which enters a recess in positively lock the tool shank therein; and I have provided a floating, resilient seat which permits free rotation to facilitate alignment of the tool recess and the cam lock, and prevents complete seating of the tool shank until the alignment is completed. I have also limited the rotation of the looking cam by providing a groove thereon which cooperates with the pilot stop of a set screw in the holder, and thus prevents overrotation of the locking cam in either direc-' tion.

My improved construction therefore permits ready interchangeability of machine tools without removal of the tool holder and ensures proper seating and locking of the machine tool shanks in the holder socket;

and many methe tool shank to and the following is a detailed description of one form of holder which embodies the fea- I tures of my invention.

Referring to the drawing, 10 designates the improved tool holder, which is seated within a spindle 11 of standard type, and

locked in the spindle by means of the usual through bolt 12, which engages a screw threaded recess 13 in the inner end of the holder; As shown in Figure 3, the tool holdmore than three times its base diameter and housed in a recess 23 aligned with the recess 20, and having the usual safety internal slots 24 for reception of the turning wrench. The other end of the cam is provided with a groove 25 set screw 27 secured in the tool holder head seats, for limiting the rotary movement of the cam.

The cam, as shown in Figure 1, is of spiral contour, the inner portion being of a diameter small enough to permit free movement of the tool shank within the socket, and the outer portion projecting into the socket to engage a cooperating reces's or slot 28 formed in the tool shank 29 of a machine tool 30; thus serving as a locking drive v cam. A bushing 31 through which the set screw 27 passes, locks the cam within the transverse recess 20. y

The operation of my improved tool holder is as follows:

The cam being in non-locking position, the

' tool shank of a machine tool is inserted in shank engages the the tool holder socket. The end of the tool spring, and freely rotates to permit alignment of the recess in the tool shank with the cam, complete seating being prevented until the alignment is completed; turning the cam then in a clock-wise direction forces the cam into the recess and also forces the tool shank rearwardly to firmly seat in' the socket against the pressure of the spring. The pilot end 26 prevents overrunning of the cam and indicates both the unlocked and the fully locked positions to the operator.

It will thus be apparent that the improved tool holder eliminates the sticking of tool shanks therein, and permits ready removal therefrom, prevents the freezing of tool shanks therein, positively locks the tool shanks in firm seating engagement with the tool holder socket, insures positioning of the locking device in either locking or unlocking position, and has no protrudingbolt heads which may endanger the operators safety.

While I have disclosed one preferred embodiment of my invention as applied on an adapter or separate tool holder, it is obvious that this means of holding and locking the tool shank may be provided on a rotatable spindle rather than on a separate holder as within which a pilotstop 26 of a.

illustrated and that various changes in structure and arrangement may be made, within the scope ofmy invention as defined in the appended claims.

I claim:

1. An adapter for machine tools having a tapered conical tool shank receiving socket, a spring seat forming the base of said socket, and a locking and driving element rotatably mounted and having a projection movable into said socket.

2. -An adapter for machine tools having a tapered conical tool shank receiving socket,

a plug mounted for rotation contiguous to a circular plug mounted for rotation contiguous to said socket, and a cam extending from said plug and projectable into said socket on rotation of said plug.

5. An adapter for machine tools having a tapered conical tool shank receiving socket, a spring seat forming the base of saidsocket,

a circular lug mounted for rotation contiguone to sai socket, a cam on said plug projectableinto said socket on rotation of said plug, a groove on said plug of predetermined length, and a stop on'said adapter positioned within said groove. 7

6. An adapter for machine tools having a. tapered conica tool shank receiving socket, a spring seat forming the base of the socket, a recess in said adapter, a circular plug mounted in said recess for rotation contiguous to said socket, a cam on said plug projectable into said socket on rotation of said plug, a groove on said plug of predetermined length, a stop element positioned in said groove, and means for rotatin said plug within said recess positioned be ow the surface of the adapter.

w 7. In combination, an adapter for machine tools having a conical tool-shank receiving socket, a resilient seat forming a base for said socket, a cam rotatably mounted in the wall of said socket for projection into the socket, and a tool having a conical shankwith an arcuate recess therein to receive said cam for urging said tool inwardl of said socket and against the action of sai seat.

8. A tool holder provided with a toolshank receiving socket having a. non-sticking tapered conical seat, and a locking and driving element rotatably mounted and having a projection adapted to be moved into or withdrawn from saidsocket by a mere rotation of said element and for engaging a recess in a tool shank.

9. A tool holder provided with a tapered conical tool-shank receiving socket, a resilient seat forming the base of said socket, and

a locking and driving element rotatably mounted and having a projection movable into said socket.

10. A tool holder provided with a tapered conical tool-shank receiving socket, a plug mounted for rotation contiguous to said socket, a cam extending from said plug and projectable into said socket on rotation of said plug, and means for limiting therotatable movement of said plug.

11. A tool holder provided with a tapered conical tool-shank receiving socket, a resilient seat forming the baseof said socket, a circular plug mounted for rotation contiguous to said socket, and a cam extending from said plug and 'projectable into said socket on rotation of said lug.

12. A tool hol er provided with a tapered conical tool-shank receiving socket, a resilient seat forming a base for said socket, a locking element rotatably mounted in the wall of said socket and having a projection movable into said socket and adapted to engage an arcuate recess in the tool shank inserted into said socket for urging said tool inwardly of said socket and against the action of said seat.

In testimony whereof I aifix my signature.

ARTHUR C. MAXFIELD. 

